I just have to add my opinion on the Phoenix lens, I bought one before I knew anything about lenses. Paid $400 for a 100-500mm manual focus. all I can say is... its a very expensive paper weight and that's about all its good for.

I have an A200 with the kit lens and a Tamron LD-Di 70-300 which I like very much. Overall it's a very good lens for the money and has surprisingly good IQ. IMO if you're on a budget, it's hard to go wrong with the this lens. Take a serious look at it before you go with the Phoenix/Cosina. Just my 2 cents.